King Charles III was officially announced as Britain’s monarch Saturday, in a ceremony steeped in ancient tradition and political symbolism — and, for the first time, broadcast live.

Charles automatically became king when his mother, Queen Elizabeth II, died on Thursday, but the accession ceremony is a key constitutional and ceremonial step in introducing the new monarch to the country.

Scores of senior politicians past and present, including Prime Minister Liz Truss and five of her predecessors, gathered in the ornate state apartments at St. James’s Palace for the meeting of the Accession Council.

They met without Charles, officially confirming his title, King Charles III. The king joined them to make a personal declaration, vowing to follow his mother’s “inspiring example” as he took on the duties of monarch.

“I know how deeply you and the entire nation, and I think I may say the whole world, sympathize with me in this irreparable loss we have all suffered," he said.

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It’s the first time the ceremony has been held since 1952, when Queen Elizabeth II took the throne.

Charles is accompanied at the ceremony by his wife Camilla, the Queen Consort, and his eldest son Prince William. William is now heir to the throne and known by the title Charles long held, Prince of Wales.

After the ceremony, an official will read the proclamation aloud from a balcony at St. James’s Palace. It will also be read out in the medieval City of London and at other locations across the U.K.

Two days after the 96-year-old queen died at Balmoral Castle in Scotland following an unprecedented 70 years on the throne, people still came in their thousands to pay their respects outside Buckingham Palace in London. The scene was repeated at other royal residences across the U.K. and at British embassies around the world.

The monarch set the tone for his reign on Friday, vowing in a televised address to carry on the queen's “lifelong service,” with his own modernizing stamp.

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Charles looked to both the past — noting his mother’s unwavering “dedication and devotion as sovereign” — and the future, seeking to strike a reassuring note of constancy while signaling that his will be a 21st-century monarchy.

He reflected on how the country had changed dramatically during the queen’s reign into a society “of many cultures and many faiths,” and pledged to serve people in Britain and the 14 other countries where he is king “whatever may be your background or beliefs.”

He also tried to overcome a reputation for aloofness in his first hours as monarch, spending time shaking hands with some of the thousands who came to leave flowers and pay tribute to the queen at the gates of Buckingham Palace. He was greeted with shouts of “Well done, Charlie!” and “God save the king!” One woman gave him a kiss on the cheek.

Britain is holding a period of mourning for the queen, with days of carefully choreographed ceremonies marking the death of the only monarch most people have ever known.

In the next few days the queen’s body will be brought from Balmoral, first to Edinburgh and then to London, where she will lie in state before a funeral at Westminster Abbey, expected around Sept. 19.

In his speech, Charles struck a personal note, speaking of his sorrow at the loss of “my darling Mama.”

“Thank you for your love and devotion to our family and to the family of nations you have served so diligently all these years,” he said, ending with a quote from Shakespeare's “Hamlet” — “May flights of angels sing thee to thy rest.’”